Effect of different synthesis temperature on the bleeding performance of polycarboxylate superplasticizer

Abstract

In this paper, polycarboxylate superplasticizers were synthesized by free radical solution polymerization under different synthesis temperature conditions. The bleeding performance of polycarboxylate superplasticizers under different synthesis temperature conditions was discussed by paste test and concrete test, and the structure of polycarboxylate superplasticizers was characterized by infrared spectroscopy (FTIR) and gel permeation chromatography (GPC). The results show that the bleeding and slump retention performance of polycarboxylate superplasticizer can be effectively improved by properly increasing the synthesis temperature, and the better synthesis temperature was 55 °C. With the temperature increase, the molecular weight of polycarboxylate superplasticizers increases first and then decreases. The infrared spectra of polycarboxylate superplasticizers synthesized at different temperatures were not significantly different.

Study on performance stability of Polycarboxylate Superplasticizer prepared at different temperatures

“…Some studies have shown that [9][10] , FeSO 4 will coordinate with the carboxyl group of acrylic acid, shift the common electron cloud of carbon carbon double bond in the monomer to carbonyl carbon, enhance the activity of double bond, and improve the conversion rate of monomer. FeSO 4 can accelerate the decomposition of hydrogen peroxide and the production of active free radicals.…”

“…In different seasons, the normal temperature ranges from 15℃ to 40℃. When polycarboxylate Superplasticizer is prepared by room temperature process, different reaction temperature will directly affect the activity of free radical and comonomer, so as to affect the performance of water reducer [7][8][9] . Therefore, the study of reaction temperature and factors affecting process temperature plays an important role in maintaining the stability of polycarboxylic acid high-performance water reducer.…”